What Happens to Human Waste After It Goes Through a Sewage Treatment Plant?

When you flush the toilet or rinse something down the drain, it鈥檚 easy to forget what happens next. But wastewater goes through a complex process before it can be safely discharged back into the environment. Let's take a look at what happens to human waste after it goes through a sewage treatment plant.

Primary Treatment

The first step in sewage treatment is called primary treatment, which separates larger solids from the liquid wastewater. Large objects like sticks and rags are removed from the wastewater with screens or grates, and the rest of the solid waste is settled out in large sedimentation tanks. This sludge is then removed and transported to landfills, where it is disposed of or further processed into fertilizer.

Secondary Treatment

After primary treatment, the wastewater goes through secondary treatment. This stage is where all the organic matter is removed from the wastewater. Wastewater is mixed with bacteria that consume the organic matter and turn it into carbon dioxide and water. The treated wastewater then goes through a clarification process, which removes any remaining solids. The solids that are removed during secondary treatment are also transported to landfills for disposal or further processing.

Disinfection and Discharge

Once the wastewater has gone through primary and secondary treatment, it鈥檚 almost ready to be discharged. However, there鈥檚 one more step to make sure it鈥檚 safe for the environment. Disinfection is the final stage in the sewage treatment process. Chlorine or another disinfectant is added to the wastewater to kill any remaining bacteria and viruses. After disinfection, the treated wastewater is discharged into rivers, lakes, or oceans.

In conclusion, human waste goes through a rigorous process before it's released back into the environment. Sewage treatment plants are critical to public health and the environment, as they help keep our waterways clean and free from harmful bacteria and viruses. The solid waste that is removed during treatment can also be recycled into fertilizer and other useful products. It's important to remember that our actions have consequences, even those as simple as flushing the toilet.